Light control?

I have a DR150 and tomorrow Im going to start flowering. I have a 5" fan and carbon filter in the tent and ducting going outside, Im using 2ft of 5" ducting down the bottom of the tent as a passive air intake. I'll have my lights on during the day for many different reasons but this suits me better, problem is the outside of the tent the sun comes up at 6am but I dont turn on my lights til 10am and some light is getting through the passive air intake, I dont live local to any grow shops to buy some more ducting, any ideas to rectify the problem??
Thanks in advance

hit the local hardware store and get dryer venting or cover the window that the light is coming in from

i agree dryer vent is your best and easiest option my friend!! G

If you made a couple turns with the duct, it will eliminate the light. As this is a passive intake it shouldn't be a big deal.